1. Field of the Invention
The present invention relates to an internal voltage generator for a semiconductor device, and in particular, to an improved variable voltage driver circuit using a current detector which is capable of variably adapting a current supply capacity to a semiconductor device by measuring voltage and current generated by an internal voltage generator.
2. Description of the Conventional Art
The voltage generator for a semiconductor device implemented by a semiconductor CMOS process is generally formed of a current mirror and a differential amplifier or a circuit generating a voltage using a ring oscillator and a charge pump and a driver generating a current used for the operation of a device based on the thusly generated voltage. At this time, in the thusly constituted conventional circuit, the operation of the voltage generator is stopped when a normal voltage is maintained using the voltage detector for an effective operation of the circuit. In addition, since there is not an information about the current used for the voltage generator, it is difficult to properly drive the current of the driver circuit. In this case, the driving capacity of the driver circuit is determined based on a simulation using a predetermined current value required for the internal operation of the circuit. If the driver circuit of the voltage generator is not properly driven based on the above-described current, an operational error of the device may occur. In order to overcome the above-described problem, the driver circuit is driven using various error checking units, for example, a FIB (Focused Ion Beam), so that the fabrication cost of the products is increased and the time required for fabricating the products is also increased, for thereby causing an inefficiency in the system.